Method and system for enhancing the intelligibility of sounds

Abstract

A method of enhancing the intelligibility of sounds including the steps of: detecting primary sounds emanating from a first direction and producing a primary signal; detecting secondary sounds emanating from the left and right of the first direction and producing secondary signals; delaying the primary signal with respect to the secondary signals; and presenting combinations of the signals to the left and right sides of the auditory system of a listener.

The invention claimed is: 
     
       1. A method of enhancing the intelligibility of sounds including the steps of:
 providing a sound detecting means which includes at least one microphone located on or within each side of a listener's head; 
 detecting sounds by way of the sound detecting means to produce a primary signal which emphasizes sounds emanating from a first direction and to produce left and right secondary signals which emphasize sounds emanating from the left and the right of the first direction respectively; 
 delaying only the primary signal with respect to the secondary signals to produce a delayed primary signal, wherein the primary signal is delayed by more than 0.7 milliseconds; 
 combining the delayed primary signal and the left secondary signal to produce a combined left signal; 
 combining the delayed primary signal and the right secondary signal to produce a combined right signal; 
 providing a signal presentation means; 
 presenting the combined left signal by way of the signal presentation means to the left side of the auditory system of the listener; and 
 presenting the combined right signal by way of the signal presentation means to the right side of the auditory system of the listener. 
 
     
     
       2. A method according to  claim 1  wherein the primary signal is delayed by 1 millisecond or more. 
     
     
       3. A method according to  claim 1  wherein the steps of producing the combined left and right signals includes the step of altering the level of the left and right secondary signals. 
     
     
       4. A method according to  claim 3  wherein the step of altering is frequency specific. 
     
     
       5. A method according to  claim 3  wherein the step of altering is dependent on the levels of the primary and secondary signals. 
     
     
       6. A method according to  claim 4  wherein the step of altering is dependent on the levels of the primary and secondary signals. 
     
     
       7. A method according to  claim 3  wherein the step of altering is controlled by the listener. 
     
     
       8. A method according to  claim 4  wherein the step of altering is controlled by the listener. 
     
     
       9. A method according to  claim 3  wherein the step of altering is controlled by a trainable algorithm. 
     
     
       10. A method according to  claim 4  wherein the step of altering is controlled by a trainable algorithm. 
     
     
       11. A method according to  claim 3  wherein the step of altering is dependent on either the level of the primary or secondary signals. 
     
     
       12. A method according to  claim 4  wherein the step of altering is dependent on either the level of the primary or secondary signals. 
     
     
       13. A method according to  claim 2  further includes the step of introducing localisation cues into the primary signal to produce a left and a right primary signal. 
     
     
       14. A method according to  claim 13  wherein the localisation cues are exaggerated. 
     
     
       15. A system for enhancing the intelligibility of sounds including: a sound detecting means which includes at least one microphone located on or within each side of a listener's head for detecting sounds to produce a primary signal which emphasizes sounds emanating from a first direction and to produce left and right secondary signals which emphasize sounds emanating from the left and the right of the first direction respectively;
 delay means for delaying only the primary signal with respect to the secondary signals to produce a delayed primary signal, wherein the delay means is arranged to delay the primary signal by more than 0.7 milliseconds; and 
 presentation means for presenting combinations of the delayed primary signal and the left secondary signal to the left side of the auditory system of a listener and the delayed primary signal and the right secondary signal to the right side of the auditory system of the listener. 
 
     
     
       16. A system according to  claim 15  wherein the delay means is arranged to delay the primary signal by 1 millisecond or more. 
     
     
       17. A system according to  claim 15  wherein the presentation means includes a loudspeaker, headphones, receivers, bone-conductors or cochlear implants. 
     
     
       18. A system according to  claim 15  which is embodied in a linked binaural hearing aid.